The brainstem contains a number of central mechanisms regulating a number of vital physiological functions. Disorders in the regulation of the cardio-pulmonary system can result in a number of pathological conditions some of which may be potentially life threatening.
Current CDs comprise one or more leads that, in use, are placed in a human heart. Removing such CD leads results in serious damage to the body, i.e., the heart, blood vessels and surrounding tissue. There is a need for CDs that do not show this disadvantage.
Research in cats has shown that breathing can be stopped by inhalation of anoxic mixtures for over 1 minute, with subsequently a severe drop in blood pressure and heart rate. Mechanical or electrical stimulation of the nasopharynx can induce a sniff- and gasp-like “aspiration reflex” (Tomori and Widdicombe, 1969, Be{hacek over (n)}a{hacek over (c)}ka & Tomori, 1995, Tomori et al. 1995, 1998, 2000). Due to resuscitation effects, the blood pressure returns to normal, heart rhythm normalizes, respiration and neuro-behavioral functions return to normal. The anesthetized cat seems to be in good condition, even after as long as three minutes without adequate blood pressure, heart rate and breathing. This experiment can be repeated over 10 times on the same cat, without any noticeable negative consequences.
Provocation of such an aspiration reflex has been indicated as a possible means for interruption of apnoea in cats (Tomori et al., 1991, 1995, Be{hacek over (n)}a{hacek over (c)}ka & Tomori, 1995, Jakus et al., 2004). Alternatively, similar resuscitation may be induced by (electro)-acupuncture, (electro)-acupressure or mechanical stimulation of the nasal philtre in cats, inducing spasmodic inspiration (Be{hacek over (n)}a{hacek over (c)}ka Tomori, 1997).
However, the current position of the published state of the art is that the typical spasmodic inspirations of the aspiration reflex provoked from the nasopharynx and oropharynx in cats are not notable in humans and in this latter species are superimposed by a strong vomiting reflex (Be{hacek over (n)}a{hacek over (c)}ka 2004).
Other researchers found reactions different from the aspiration reflex in humans in response to stimulation of the upper airways with high-frequency oscillating air pressure (Henke & Sullivan, 1992).
PCT/NL2006/000599, which has not been published prior to the priority date of the application relating to the present invention, describes the surprising discovery that a resuscitating stimulation of the brainstem with an induced aspiration reflex in order to obtain resuscitating physiological effects also works in human beings. That document also describes some devices designed for treating apnoea and related cardio-respiratory syndromes in humans via activation of the respiratory centre of the brainstem followed by an induced aspiration reflex. However, this document is silent as to possible application as a cardiovertor/defibrillator.
WO2006/115877 discloses an apparatus for stimulating the vagal nerve of a human being for treatment of atrial fibrillation.